Seth is the protagonist of the novel and its narrator. Readers learn in the first few pages that Seth’s father died when Seth was seven. In the last chapter, they learn that this narrative is a project recommended for him by a grief counselor after the death of his best friend Jimmy Winter when Seth is 17. Seth is a passive, kind boy who is deeply affected by his father’s death.

Seth’s character develops a great deal during the course of the story, which covers five years—sixth grade through junior year in high school. Thanks to his friendship with Jimmy, Seth becomes absorbed in the game of baseball, learning about its history and acquiring real athletic skill. Seth also develops into a leader on the field, something else he learns from Jimmy.

Seth can be woefully insecure at times, doubting his intellectual and athletic abilities. Over time, however, his confidence builds, and he comes to have clear ideas about what he can accomplish in the field and in the classroom. Seth is tremendously loyal to his friends, his team, and above all his mom. This loyalty is apparent to others, who often rely upon him in difficult situations.